Hydrogen and carbon isotopic ratios of polycyclic aromatic compounds in two CM2 carbonaceous chondrites and implications for prebiotic organic synthesis

Huang, Yongsong; Aponte, José C.; Zhao, Jiaju; Tarozo, Rafael; Hallmann, Christian

doi:10.1016/j.epsl.2015.06.027

Cited by 21 publications

(27 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Pyrolysis of alkylated PAHs could result in the unalkylated forms during solar T-Tauri phase flares (Hartmann et al 1993). Such a nebular environment could also produce hydrogen-deuterium exchange resulting in D enrichments in these organic materials, which have been observed in several polycyclic aromatic compounds in Murchison (Huang et al 2015). As we do not have the H isotopic compositions of the thiophenes in our subset that would point with certainty toward a nebular origin of these species, the possibility of the formation of these sulfur-containing organic materials in the asteroid parent body cannot be ruled out.…”

Section: L-raman Datamentioning

confidence: 99%

A XANES and Raman investigation of sulfur speciation and structural order in Murchison and Allende meteorites

Bose

Root

Pizzarello

2017

Meteorit & Planetary Scien

View full text Add to dashboard Cite

Insoluble organic matter (IOM) and hydrothermally treated IOM extracted from two carbonaceous chondrites, Murchison and Allende, was studied using sulfur K‐edge XANES (X‐ray absorption near edge structure) and μ‐Raman spectroscopy, with the aim to understand their IOM's sulfur speciation and structural order, and how aqueous alteration or thermal metamorphism may have transformed these materials. We found that the sulfur‐functional group chemistry of both the Murchison IOM and hydrothermally treated IOM samples have a large chemical variability ranging from oxidation states of S−2 to S+6, and exhibit a transformation in their oxidation state after the hydrothermal treatment (HT) to produce thiophenes and thiol compounds. Sulfoxide and sulfite peaks are also present in Murchison. Sulfates considered intrinsic to Murchison are most likely preaccretionary in nature, and not a result of reactions with water at high temperatures on the asteroid parent body. We argue that the reduced sulfides may have formed in the CM parent body, while the thiophenes and thiol compounds are a result of the HT. Micro‐Raman spectra show the presence of aliphatic and aromatic moieties in Murchison's material as observed previously, which exhibits no change after HT. Because the Murchison IOM was modified, as seen by XANES analysis, absence of a change observed using micro‐Raman indicated that although the alkyl carbons of IOM were cleaved, the aromatic network was not largely modified after HT. By contrast, Allende IOM contains primarily disulfide and elemental sulfur, no organic sulfur, and shows no transformation after HT. This nontransformation of Allende IOM after HT would indicate that parent body alteration of sulfide to sulfate is not feasible up to temperatures of 300°C. The reduced sulfur products indicate extreme secondary chemical processing from the precursor compounds in its parent body at temperatures as high as 624°C, as estimated from μ‐Raman D band parameters. The Raman parameters in Allende IOM that was interpreted in terms of amorphous carbon with regions of large clusters of benzene rings, was transformed after the HT to those with fewer benzene rings.

show abstract

Section: L-raman Datamentioning

confidence: 99%

A XANES and Raman investigation of sulfur speciation and structural order in Murchison and Allende meteorites

Bose

Root

Pizzarello

2017

Meteorit & Planetary Scien

View full text Add to dashboard Cite

show abstract

“…Sample preparation and chemical treatment followed the procedures described in Huang et al (2007Huang et al ( , 2015 and Gao et al (2011). Samples were first cleaned three times with dichloromethane to remove any possible surface contamination and freeze-dried for 12 h. The dried samples were ground in a ceramic mortar and pestle, weighed to collect 40-60 g and then mixed with baked sands (2:1) to enhance the mobility of organic compounds.…”

Section: Sample Preparation and Isotopic Analysismentioning

confidence: 99%

Neogene vegetation shift in the Nepalese Siwalik, Himalayas: A compound‐specific isotopic study of lipid biomarkers

Neupane

Gani

et al. 2019

The Depositional Record

Self Cite

View full text Add to dashboard Cite

The late Neogene vegetation change of C 4 plants replacing C 3 plants is widely documented across the world. This vegetation shift has been particularly well-documented in the Himalayan foreland based on δ 13 C isotopic data from palaeosol carbonates and bulk organic matter in the Siwalik sedimentary rocks of Pakistan, India and Nepal, showing asynchronous expansion of C 4 plants between 8 and ~5 Ma, 9 and 6 Ma, and around 7 Ma, respectively. In this study, compound-specific isotopic analysis of lipid biomarkers extracted from shale and palaeosols in the palaeomagnetically age-constrained Nepalese Siwalik is utilized to better understand this vegetation shift. This is the first comprehensive lipid biomarker study in the Nepalese Siwalik, with new isotopic results from the previously undocumented Karnali River section. The δ 13 C n-alkane (C 27-31 ) results from the Surai Khola section suggest C 3 plants were dominant between 12 and 8.5 Ma. A stepwise expansion of C 4 plants that started gradually at 8.5 Ma escalated rapidly after 5.4 Ma, so that by 5.2 Ma C 4 vegetation dominated the landscape. This dramatic ecological shift at the Miocene-Pliocene boundary was likely linked with an intriguing tectonic-climate coupling in the Himalayan-Tibetan region, prompting wetter summers and drier winters that drove C 4 grass expansion.However, in the Karnali River section, the data show no clear sign of C 4 plant expansion until 5.2 Ma (youngest sample age). In the two study locations separated laterally by ~200 km along tectonic-strike, this different trend of vegetation change likely indicates local controls like river-catchment influence. However, it is possible that, similar to the Surai Khola section, C 4 plants dominated after 5.2 Ma in the Karnali River section. This study also suggests that the past vegetation makeup of an area is better reconstructed using isotopic signatures of molecular markers than of bulk organic matter or pedogenic nodules.

show abstract

“…Fatty acids and polycyclic aromatic hydrocarbons (PAHs), such as 4-methyl phthalic acid, have been previously found in meteorites [30], but not so often in these impact glasses.…”

Section: Darwin Glasses (Dgs)mentioning

confidence: 99%

Detection of organic compounds in impact glasses formed by the collision of an extraterrestrial material with the Libyan Desert (Africa) and Tasmania (Australia)

et al. 2018

View full text Add to dashboard Cite

Impact glasses are rich silica melted formed at high temperature and pressure by the impact of an extraterrestrial body on Earth. Here, Libyan Desert glasses (LDGs) and Darwin glasses (DGs) were studied. Two non-destructive analytical techniques were used to detect and characterize organic compounds present in their inclusions: Raman spectroscopy and scanning electron microscopy coupled to energy-dispersive X-ray spectroscopy (SEM-EDS). Phytoliths, humboldtine, palmitic acid, myristic acid, oleic acid, 4-methyl phthalic acid, and S-H stretching vibrations of amino acids were identified. The presence of these particular organic compounds in such materials has not been reported so far, providing information about (a) the ancient matter of the area where the impact glasses were formed, (b) organic matter belonging to the extraterrestrial body which impacted on the Earth, or (c) even to current plant or bacterial life, which could indicate an active interaction of the LDG and DG with the surrounding environment. Moreover, the identification of fullerene allowed us to know a pressure (15 GPa) and temperatures (670 K or 1800-1900 K) at which samples could be subjected.

show abstract

Hydrogen and carbon isotopic ratios of polycyclic aromatic compounds in two CM2 carbonaceous chondrites and implications for prebiotic organic synthesis

Cited by 21 publications

References 46 publications

A XANES and Raman investigation of sulfur speciation and structural order in Murchison and Allende meteorites

A XANES and Raman investigation of sulfur speciation and structural order in Murchison and Allende meteorites

Neogene vegetation shift in the Nepalese Siwalik, Himalayas: A compound‐specific isotopic study of lipid biomarkers

Detection of organic compounds in impact glasses formed by the collision of an extraterrestrial material with the Libyan Desert (Africa) and Tasmania (Australia)

Contact Info

Product

Resources

About